Hydroxy-aromatic alkylene di-imino



Reiuued Jan. 12, 1954 'DI-ACETIC ACIDS AND SALTS Frederick C. Bersworth, Verona, N. J.

No Drawing. Original No. 2,624,760, dated January 6, 1953, Serial No. 193,542, November 1, 1950. Application for reissue August 17, 1853,

Serial No. 374,837 4 6 Claims.

Matter enclosed in heavy brackets appears in the original patent but forms no part gm; reissue specification; matter printed in italics indicates the additions made by reissue.

This invention relates to chelating compounds tor metal ions in aqueous solutions and has for its object the provision ot a metal ion chelating compound consisting of a hydroxy-aromatic alkylene diamine diacetic acid or alkali metal,

ammonium or amine salt of said acid.

Another object 'is to provide a bactericidally active alkylene diamine diacetlc acid compound which is also active as a metal ion chelating agent in aqueous solutions.

Still another object is to provide water soluble phenolic alkylene diamine diacetic acid compounds which are bactericidally active as well as reactive as metal ion chelating compounds.

Other objects will be apparent as the invention is more fully hereinafter disclosed.

In accordance with these objects I have discovered that where one of the amino hydrogens in each of the amino nitrogen group or an allphatic alkylene diaminc are displaced by a substituted phenyl group and the remaining amino hydrogens are displaced by acetic acid groups, the resultant [di-phenyl alkylene diamine] disubstituted phenul diacetic [acid is] acids are water soluble and in aqueous solution are good metal ion chelating agents. g Compounds of the type of the present invention iall generally under the structural formula:

XQQI-alkyleneh-IIQX wherein x is selected from the group consisting of hydrogen, alkyl, alkoxyl, hydroxyl and halogen, at least one it being a halogen atom; n is a positive integer selected from the group consisting of l to [,A represents acetic acid or a homologue acid] A is from the group consisting of CHzCOOH, -CH2CH2COOH, and the alkali metal, ammonium and amine salts thereof; and wherein alkylene represents ethylene, propylene or trimethylene.

CHI-COONI CHrCOONl CHrCH| x x 5 v ,1

x x O 0 OI. OH HO er ors-0m n x JJH: C II 6H: I o o 0 o .OH H0 x N FHrCH N x x infci' :11.

It is impossible from present data to decide between these two possibilities.

However, with certain metals, such as nickel, cobalt and iron, it is known that six complexing groups are quite common. Therefore, it is believed that the greater stability of these phenolic chelates is due to the participation or the phenolic group in chelation with the metal normally to give metalchelates with structures such as:

carboxyl groups. two phecan:

tion effect, I may use any hydroxy aromatic compounds without limitation as to the location of the hydroxyl group and/or other substituents.

While the alkali metal salts are quite soluble in watenthe chelates are much less soluble in neu-- tral solutions and the compounds may, therefore. he used to precipitate such metal ions in the form of the chelate. However, in alkaline solutions the chelates show an unexpected solubility and which is thought to be due to secondary salt formation either as hydrates or phenolate's or both.

The acids themselves as well as the amine salts are quite soluble in organic solvents and oils and so are the chelates. These compound are, therefore. very useful when it is desired to add metal atoms in non-ionic form to oil. grease or waxes. The compounds of this invention may also be solubilised by means of sulfonation or sulfoalkylation by reacting the acids of these compounds with sulfuric acid or other sulfonating agents.

In compounds of this type, the simplest compounds to prepare and describe, by way of example but not by way of limitation, are those derived from ethylene diamine diacetic acid. There are several alternative ways to prepare these compounds. one of which is as follows:

Exampleli Two moles of o-nitrosophenol are dissolved in alcohol and treated with an excess amount of cupric or nickelous hydroxide until the nitrosophenol has been completely converted into a copper or nickel complex generally considered to have the following structure:

' After filtering oil the excess metal hydroxide, the alcoholic solution of this complex is added slowly to a 0% aqueous-alcohol solution containing one mole of ethylene diamine while cooling the solution to maintain a reaction temperature of about 85 C.

The resulting [di(o-nitrosophenol) ethylene diamine] di-(o-nitrosophenul) -ethylenediamine 1 metal complex is then decomposed by passing hydrogen sulfide through the solution to precipitate the copper or nickel sulfide and the solution is filtered and the hydrogen sulfide present therein is driven oif.

The resulting [di (o-nitrosophenol) ethylene diamine] di- (o-nitrosophenul) -ethvlenediamine is catalytically reduced to the [di(amino ophenyl) ethylene diamine] di-(o-nminophenubethwienediamine and this compound is recovered from solution as the di-hydrochloride.

The di-hydrochloride compound is dissolved in water and 1| converted to the di-diasonium salt by treatment with NaNOrand H01 in accordance with known methods and is permitted to hydrolyse in aqueous solution under controlled temperature conditions to the di-(o-hydroxyphenyl) ethylene diamine, according to known reactions.

The aqueous solution of this [di (o-hydroxyphenyl) ethylene diamine] di-(o-hydrotyphemm-ethylenediamine compound is then carboxylmethylated in accordance with the process described in my Patents Nos. 2,387,735 and 2,407,645 using two molar weights-each of Net!!! and 01120 and sumcient caustic soda to give a pliaof about 10 and a reaction temperature of 8 5' C.

The resulting reaction solution is then filtered free of insolubles and is neutralized with HCl .and the [di (o-hydroxyphenyl) ethylene di amine] dz (o-hydroxyphenul) -ethuleaediamine diacetic acid product is recovered therefrom by evaporation to crystallization. This compound has the structural formula:

CHrCOOH OKs-COOK QLMMLQ This compound is a very powerful chelating agent for all di-valent heavy metals forming chelates which are soluble in water. The phenolic groups are reactive as a bastericide and fungicide irrespective of the pH of the solution.

On chlorination of the phenolic groups by passing chlorine through an aqueou solution of the di-alkali metal salt of [di (o-hydroxyphenyl) ethylene diamine] di-(o-hydrozuphenyl) ethyienediamine diacetlc acid, four (4) gramatoms of chlorine are rapidly absorbed by one mole of the compound yielding on acidification and crystallization chlorinated compounds of the type.

cur-coon cal-coon c NCHr-CHr-N 01 be obtained forming compounds wherein each aromatic ring is chlorinated as follows:

c on

This completely chorinated compound is an excellent bastericide and fungicide and its copper chelate compound is very destructive to lower forms of plant life such as algae and fungi and shows promise as an impregnating agent in wood and cellulosic products to inhibit bactericidal and fungicidal action therein and natural waters to inhibit algae growth therein.

An alternative method of producing the [di (tetra chlorophenyl) thylene diamine diacetic acid] di-(tetrachlorophenyl) -ethwlenediaminediacetic acid above described is to treat one mole of the [N,N' di (penta chlorophenyl) ethyl- Cl Cl This amino-copper complex is suspended in water and treated with 1125, preferably in the presence of sufficient alcohol to solubilize a part of the complex, until the copper is entirely removed as an insoluble sulfide. The resulting [di-(hydroxy tetra chlorophenyl) ethylene diamine] di (hudrozy-tetrachlorophenyl) -ethylenediamine is put into solution by adding more alcohol to the solution, the copper sulfide is removed therefrom by filtration and the alcoholwater solution removed by evaporation. The solid residues are then dissolved in 80% tertiary butyl alcohol, filtered to remove the last traces oi insolubles and the amine is [carboxy-methylated] carboxymethylated as hereinabove described, by the addition of two moles each 01 sodium cyanide and CHcO to the solution while maintaining an alkaline pH in the reaction solution and a reaction temperature of about the boiling point of the solution.

The gaseous ammonia reaction product is rapidly withdrawn from the reaction solution during the carboxymethylation process to avoid the formation oi side reaction products. The alkali metal salt of the diacetic amino acid may be crystallized from the reaction solution by slow evaporation and filtration of crystals as formed. The diacetic amino acid-,is recovered from the reaction solution by acidification of the solution to a pH of about 3 with H01, at which it precipitates. The structural formula or the amino acid has been given above.

Example 11'.

As a second example of the present invention, I will describe the process of forming the [di- (o,o'-dimethoxy' p-toluidine) ethylene diamine] di (0,0' dimethoxy p-toluidine)-ethylenediamine diacetic acid, which may also be called N,N' di (2 hydrozy d-methvl-ii-methoxflethylenediaminediacetic acid. In the production of this compound two (2) moles of o,o'-dimethoxy p-toluidine are dissolved in pyridine solution and are treated under pressure with one mole of ethylene dichloride at a temperature of about 100 to 140 C., to form the [di(o,o'-dimethoxy p toluidine] di (0,0' dimethoxy-p- This complex on treatment with H28 in aqueous solution is converted into the copper-free di- (o-hydroxyphenyl) ethylene diamine which on carboxymethylation as above described is converted into corresponding diacetic acid salt having the formula:

OCH: CHa-COON.

0 I GHs-OOONI H1O N-CHr-CHr-N OH:

This product is the alkali metal salt. The acid of the compound is precipitated at about pH 3.

On chlorinating the diacetic acid or salt two atoms of chlorine may be introduced into each aromatic ring giving a chlorinated salt which on acidification yields the following diacetic acid amino compound:

- I CHrOOOH cal-coon C] mc- N-CHr-CHry -om 01 a n l Likewise in Example I, propylenediamine may be substituted for ethylene diamine in equivalent molar amounts and in examples given to form. by the same procedure, the analogous propylene diamine diacetic acid compounds.

Example 1V Also trimethylene diamine may be substituted in the examples given in place 01 ethylene diamine to form the analogous trimethylene diamine diacetic acid compounds. This compound is slightly less effective as a chelating compound than the ethylene and propylene analogues but nevertheless is quite useful in accordance with this invention.

In the above identified compounds it is to be understood that in the aromatic ring it is desirable for germicidal use to have at least one chlorine atom in the ring and that for better germicidal properties it'is desirable to have at least one chlorine and one hydroxyl group in the toluidine) ethylene diamine which is isolated from solution as the monohydrate after removal of solvent and pouring the product in water.

On solution of this compound in a water solution of a cupric salt with heating to a refluxing temperature and with vigorous agitation, using an excess of the cupric salt over that theoretically required, there is formed the copper complex having the formula:

aromatic ring. The remaining positions of the ring may be hydrogen or any substituted group for hydrogen which may be a halogen atom.

It is believed apparent to those skilled in the art from the above disclosure and specific examples given that substantially any aliphatic alkylene polyamine may be substituted for ethylene diamine in the described process to form thereby an analogous series of di-phenyl substituted amines which on [carboxy-methylating] carbozumethylaflng to a carboxylic acid after the substitution therein ,0! e hrdrozyl group in each benzene ring end/or [hslogenote] halogenating the ring will yield enclogous, chemical compounds withsimilnrchemicel properties. Accordingly, all compounds are contemplated as within the scope of the invention Is may fall within the scope of the following claims.

. Whotiacloimedis:

1. The compounds conforming to the following formula:

x x g x x A i XQiMi-NQX y no H whereinalkyleneisoneofthegroupconsisting of -CH2.CHa; and

A is one of the group consisting of --CH:.COOH and -CI-h.CH2.COOH; n is a. positive integer selected from the group consisting of 1 to 5; and X is a. member of the group consisting of H. halogen, lower alkyl and alkoxyl. and the alkali metal, ammonium and amine salts thereof.

2. :lhe compound conforming to the following formula:

OHI'COOH CHs-OOOH LWWL 8. The compound conforming to the following formula:

CHI'COOH CHrCOOH CIQLCHPWLQQ 4. The compound conforming to the following formula:

GHQ-COOK One-COOK CI Cl (ll O] O N- CHa- CHr N l Cl H H I e. The compound conforming to the following formula:

CHrCOOK CEr-OOOH ocin oon.

N-CH|-CH|-N on,

n n 6. The compound conforming to the following formula:

- CHrCOOK CHrC'OOH OCH:

OCH: 0]

OH N'CHrCHg-N H n i FREDERICK C. BERSWORTH.

References Cited in the file of this potent or the original patent UNITED STATES PATENTS Number Name 1 Date 868,294 Schmidlin Oct. 15, 2,195,974 Reppe et a1. Apr. 2, 1940 2,489,363 Bersworth Nov. 29, 1949 FOREIGN PATENTS Number g Country Date 18,095 Great Britain of 1913 642,244 Germany Mar. 6, 1937 OTHER REFERENCES Alphen: Chem. Abs., vol. 38, col 4943 (1944). Bischofl et al.: Bellstein (Handhuch, 4th ed), vol. 12, page 547, (1929). 

